Electronic devices, such as personal computers, laptops, mobile phones, and the like are increasingly equipped with touch screens or similar interfaces that enable a user to provide input by writing or drawing with a stylus, pen, or other pen-like device. For instance, tablet computers, which include touch screens as the primary user interface, have become popular alternatives to conventional laptops with keyboards, mice, etc. The ability to draw or write by hand on the touch screen offers substantial flexibility regarding possible inputs. However, user interfaces of many modern applications do not easily accommodate writing and drawing during normal use. For example, some applications require a user to select a particular button in order to activate a pen-compatible mode, or may simply not support pen input in a useful way.